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Dataset Overview | National Centers for Environmental Information (NCEI)

Current velocities as a function of depth measured by lowered ADCP, LADCP, on the research vessel Hugh R. Sharp in the Mid-Atlantic Bight from 2017-08-26 to 2017-09-03 (NCEI Accession 0209236)

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This dataset contains current velocities taken by lowered ADCP during research cruise conducted on the research vessel Hugh R. Sharp from late August to early September 2017 by the University of Rochester (J. Kessler) and the U.S. Geological Survey (USGS; C. Ruppel) with funding from the U.S. Department of Energy (DE-FE0028980 and DE- FE0026195, respectively) focused on water column methane dynamics in the U.S. Mid-Atlantic Bight between just north of Washington Canyon and Cape Hatteras, mostly at water depths from ~100 m to 1500 m. A critical component of this study was the acquisition of water column data along transects arrayed roughly perpendicular to the shelf-break and from shallow to deeper depths on the uppermost continental slope. This dataset reports lowered ADCP (LADCP) measurements made simultaneous with CTD casts on these transects. The LADCP data were collected using approved LADCP protocols and equipment using an instrument owned and operated by the USGS and mounted on the CTD carousel during most CDT casts. The LADCP data were combined with other cruise datasets, including positional information from the CTD files and conventional ADCP data collected by R/V Hugh R. Sharp's hull-mounted instrumentation, to produce current speed vectors as a function of depth for most of the CTD casts. A recent version of the LADCP-community-standard Lamont-Doherty Earth Observatory Matlab-based processing package (version IX_13) was used to process the LADCP data. The files in this release include an informational header providing date, time, and location of the CTD casts for the corresponding LADCP measurements and the processed data for the depth below sea surface and calculated current velocity components. Data are in text format.
  • Cite as: Ruiz-Angulo, Angel; Ruppel, Carolyn D.; Hatcher, Gerald; Kessler, John D. (2020). Current velocities as a function of depth measured by lowered ADCP, LADCP, on the research vessel Hugh R. Sharp in the Mid-Atlantic Bight from 2017-08-26 to 2017-09-03 (NCEI Accession 0209236). [indicate subset used]. NOAA National Centers for Environmental Information. Dataset. https://www.ncei.noaa.gov/archive/accession/0209236. Accessed [date].
gov.noaa.nodc:0209236
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Distributor NOAA National Centers for Environmental Information
+1-301-713-3277
NCEI.Info@noaa.gov
Dataset Point of Contact NOAA National Centers for Environmental Information
ncei.info@noaa.gov
Time Period 2017-08-26 to 2017-09-03
Spatial Bounding Box Coordinates
West: -74.8378
East: -74.1552
South: 35.524
North: 37.535
Spatial Coverage Map
General Documentation
Publication Dates
  • publication: 2020-04-16
Data Presentation Form Digital table - digital representation of facts or figures systematically displayed, especially in columns
Dataset Progress Status Complete - production of the data has been completed
Historical archive - data has been stored in an offline storage facility
Data Update Frequency As needed
Supplemental Information
Submission Package ID: AHUM32
Purpose These data were collected to support a study of water column methane concentrations, methane carbon isotopic signatures, and oxidation rates on the U.S. Mid-Atlantic margin at distinct locations along transects down the upper continental slope in areas with known seafloor gas seepage and in background areas with no seepage.
Use Limitations
  • accessLevel: Public
  • Distribution liability: NOAA and NCEI make no warranty, expressed or implied, regarding these data, nor does the fact of distribution constitute such a warranty. NOAA and NCEI cannot assume liability for any damages caused by any errors or omissions in these data. If appropriate, NCEI can only certify that the data it distributes are an authentic copy of the records that were accepted for inclusion in the NCEI archives.
Dataset Citation
  • Cite as: Ruiz-Angulo, Angel; Ruppel, Carolyn D.; Hatcher, Gerald; Kessler, John D. (2020). Current velocities as a function of depth measured by lowered ADCP, LADCP, on the research vessel Hugh R. Sharp in the Mid-Atlantic Bight from 2017-08-26 to 2017-09-03 (NCEI Accession 0209236). [indicate subset used]. NOAA National Centers for Environmental Information. Dataset. https://www.ncei.noaa.gov/archive/accession/0209236. Accessed [date].
Cited Authors
Principal Investigators
Collaborators
Contributors
Resource Providers
Points of Contact
Publishers
Acknowledgments
  • Related Funding Agency: U.S. Department of Energy
  • Related Funding Agency: US DOI; US Geological Survey
Theme keywords NODC DATA TYPES THESAURUS NODC OBSERVATION TYPES THESAURUS WMO_CategoryCode
  • oceanography
Global Change Master Directory (GCMD) Science Keywords
Data Center keywords NODC COLLECTING INSTITUTION NAMES THESAURUS NODC SUBMITTING INSTITUTION NAMES THESAURUS Global Change Master Directory (GCMD) Data Center Keywords
Platform keywords NODC PLATFORM NAMES THESAURUS ICES/SeaDataNet Ship Codes
Instrument keywords NODC INSTRUMENT TYPES THESAURUS Global Change Master Directory (GCMD) Instrument Keywords
Place keywords NODC SEA AREA NAMES THESAURUS Global Change Master Directory (GCMD) Location Keywords
Project keywords Provider Keywords
Keywords NCEI ACCESSION NUMBER
Use Constraints
  • Cite as: Ruiz-Angulo, Angel; Ruppel, Carolyn D.; Hatcher, Gerald; Kessler, John D. (2020). Current velocities as a function of depth measured by lowered ADCP, LADCP, on the research vessel Hugh R. Sharp in the Mid-Atlantic Bight from 2017-08-26 to 2017-09-03 (NCEI Accession 0209236). [indicate subset used]. NOAA National Centers for Environmental Information. Dataset. https://www.ncei.noaa.gov/archive/accession/0209236. Accessed [date].
Access Constraints
  • Use liability: NOAA and NCEI cannot provide any warranty as to the accuracy, reliability, or completeness of furnished data. Users assume responsibility to determine the usability of these data. The user is responsible for the results of any application of this data for other than its intended purpose.
Fees
  • In most cases, electronic downloads of the data are free. However, fees may apply for custom orders, data certifications, copies of analog materials, and data distribution on physical media.
Lineage information for: dataset
Processing Steps
  • 2020-04-16T23:58:22Z - NCEI Accession 0209236 v1.1 was published.
Output Datasets
Lineage information for: dataset
Processing Steps
  • Parameter or Variable: CURRENT SPEED - EAST/WEST COMPONENT (U) (calculated); Units: m/s; Observation Category: in situ; Sampling Instrument: LADCP; Sampling and Analyzing Method: Raw data were collected by USGS researchers C. Ruppel and G. Hatcher on the R/V Sharp, with shoreside support from M. Martini, J. Borden, and K. Rosenberger from the USGS. The measurements were made using a Teledyne RDI Workhorse 300 kHz ADCP unit #WH2624 (owned by USGS Woods Hole) in a deepwater housing mounted within the outer ring but outside the bottles on the R/V Sharp's CTD carousel as part of most CTD casts during the cruise. No LADCP was run for CTD#8, which was conducted in an estuary. No LADCP data were obtained for CTD#3. The LADCP data reported here correspond to CTD #5 through #29, with the exception of #8, #14, and #21. Before the cruise, the ADCP’s magnetic compass was calibrated by J. Borden in parking lot at the Marine Operations Facility at USGS Woods Hole. Only one battery pack was used for the entire cruise, and the pressure case was never opened. Therefore, Borden’s calibration should be sufficient. The ADCP was mounted on the carousel downward looking, and a command file written by J. Borden at USGS Woods Hole was used to record data. Data were collected at 1 s per ping and 1 ping per ensemble, with bin size set to 800 cm and max radial water velocity set at 176 cm/s. Data were recorded with speed of sound assigned as 1500 m/s and in the narrow band mode for the ADCP, but with 10% extended range. The USGS used a NTP server to set LADCP time to GPS satellite time before each CTD cast. After a cast, data were downloaded to a PC laptop. Processing of the LADCP data to derive meaningful current speed vectors and depths was completed by Angel Ruiz-Angulo using the Lamont Doherty Earth Observatory (LDEO) software package, version IX_13 (Thurnherr, 2011), incorporating bottom tracking, GPS (from related CTD time series), and supplementary data from the hull mounted RDI Workhorse 300 kHz ADCP to constrain the inversion model. CTD data can be accessed at: https://accession.nodc.noaa.gov/0209090. Original LADCP data are available from the USGS (cruppel@usgs.gov).; Data Quality Method: Calculated data were assessed for reasonableness based on expected values of current velocities. Maximum error in component velocities is set at 0.5 m/s. Maximum variability in angular velocity w is set at 0.2 m/s. During the cruise, diagnostic programs were run on the LADCP unit prior to taking any measurements on each day. The LADCP passed all of these tests every time they were attempted. The LADCP unit at times interfered with the R/V Sharp’s altimeter (200 kHz) on the CTD carousel. This is a known issue documented in Thunherr et al.’s guide to LADCP (IOCPP report 14, ICPO Pub Series 134, 2010, “The GO-SHIP Repeat Hydrography Manual: A Collection of Expert Reports and Guidelines”)…Publication is called: “A Manual for Acquiring Lowered Doppler Current Profiler Data”..
  • Parameter or Variable: CURRENT SPEED - NORTH/SOUTH COMPONENT (V) (calculated); Units: m/s; Observation Category: in situ; Sampling Instrument: LADCP; Sampling and Analyzing Method: Refer to "sampling and analyzing method" for Current Speed - East/West Component in this dataset.; Data Quality Method: Refer to data quality method for "Current Speed - East/West Component" in this dataset..
  • Parameter or Variable: DEPTH - OBSERVATION (measured); Units: m; Observation Category: in situ; Sampling Instrument: LADCP; Sampling and Analyzing Method: Refer to "Sampling and Analyzing Method" for Current Speed - East/West Component in this dataset.; Data Quality Method: Calculated data were assessed for reasonableness based on known depths at the location of the CTD casts..
  • Parameter or Variable: File header (calculated); Units: ---; Observation Category: other; Sampling Instrument: other; Sampling and Analyzing Method: The file headers were generated from the original data (refer to "sample and analyzing method" for the Current Speed-East/West Component in this dataset). The headers include: CTD cast #, start and end time for the LADCP recording, start and end position in geographic coordinates (WGS84), magnetic deviation, start and end depths for LADCP, information about data processing thresholds, and then particulars about the ship's speed, water depth and instrument depth, number of LADCP recorded ensembles used in processing, and the computer used for processing and the processing speed.; Data Quality Method: The header is automatically generated by the LDEO processing routines as modified for this cruise and this dataset by Angel Ruiz Angulo..
Acquisition Information (collection)
Instrument
  • ADCP
Platform
  • R/V Hugh R. Sharp
Last Modified: 2023-09-22T13:19:13Z
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